The structure of integument and wax glands of Phenacoccus fraxinus(Hemiptera:Coccoidea:Pseudococcidae)

Using scanning electron microscopy and optical microscopy,we studied the structure of the integument and wax glands of the mealybug,Phenacoccus fraxinus Tang(Hemiptera:Coccoidea:Pseudococcidae).We observed the ultrastructure of four wax pores including trilocular,quinquelocular,and multilocular pores as well as tubular ducts,recording characteristics of their structure,size and distribution.We found that that the integument of the mealybug consists of three main layers-the procuticle,epidermis and basement membrane-and four sub-layers of the procuticle-the epicuticle,exocuticle,endocuticle and formation zone.The wax-secreting gland cells were closely arranged in epidermis.All of them were complex and composed of one central cell and two or more lateral cells.These complex cells possess a large common reservoir for collection and storage.Synthesized by the glandular cells,the wax is excreted outside integument through canals.

Selection of reference genes for RT-qPCR analysis of Phenacoccus solenopsis(Hemiptera: Pseudococcidae) sex-dimorphic development

Mealybugs, such as Phenacoccus solenopsis, are highly sexually dimorphic. Winged adult males present such remarkable morphological differences from females that, to the untrained eye, conspecific adults of both sexes of P. solenopsis may be considered as two different insect species. A method to investigate sex-dimorphic mechanisms is by evaluating gene expression using RT-qPCR. However, the accuracy and consistency of this technique depend on the reference gene(s) selected. In this study, we analyzed the expression of 10 candidate reference genes in male and female P. solenopsis at different development stages, using common algorithms including the ?Ct method, NormFinder, geNorm, BestKeeper, and a web-based analysis tool, RefFinder. The results showed that EF1-β, RP-L32 and RP-18 S were selected as the most stable genes by both the ?Ct method and NormFinder; TUB-α was the most stable gene identified by BestKeeper; and RP-L40 and RP-L32 were the most stable genes ranked by geNorm. RefFinder, a comprehensive analysis software, ranked the ten genes and determined EF1-β and RP-L32 as the most suitable reference genes for the various developmental stages in male and female P. solenopsis. Furthermore, the two most suitable reference genes were validated by examining expression of the juvenile hormone acid O-methytransferase(JHAMT) gene. Results of the validation portion of the study showed that JHAMT expression was sex-biased towards males and exhibited a dynamic and classic expression pattern among the P. solenopsis developmental stages. The results can help further our knowledge on the molecular mechanisms underlying sexual dimorphic development in P. solenopsis.

The structure of integument and wax glands of Phenacoccus fraxinus(Hemiptera:Coccoidea:Pseudococcidae)

Using scanning electron microscopy and optical microscopy,we studied the structure of the integument and wax glands of the mealybug,Phenacoccus fraxinus Tang(Hemiptera:Coccoidea:Pseudococcidae).We observed the ultrastructure of four wax pores including trilocular,quinquelocular,and multilocular pores as well as tubular ducts,recording characteristics of their structure,size and distribution.We found that that the integument of the mealybug consists of three main layers-the procuticle,epidermis and basement membrane-and four sub-layers of the procuticle-the epicuticle,exocuticle,endocuticle and formation zone.The waxsecreting gland cells were closely arranged in epidermis.All of them were complex and composed of one central cell and two or more lateral cells.These complex cells possess a large common reservoir for collection and storage.Synthesized by the glandular cells,the wax is excreted outside integument through canals.

Range expansion of the invasive cotton mealybug, Phenacoccus solenopsis Tinsley: An increasing threat to agricultural and horticultural crops in China

The globally invasive cotton mealybug Phenacoccus solenopsis Tinsley,has recently invaded several Chinese regions,and continues to expand its range.This mealybug is a polyphagous insect pest,with at least 200 host plants from 63 families,including cotton,food crops,fruits,ornamental plants,tobacco,and vegetables.Here,we describe the first finding of P.solenopsis in Shandong Province,and investigate the abundances of its natural enemies(predator Coccinella septempunctata L.and parasitoid Aenasius bambawalei Hayat).All three species were detected from ornamental and weed species in Linyi,Shandong,in September 2018,and were positively identified using DNA barcoding.BLAST analysis revealed significant identity(99.38-100%) between sequences of P.solenopsis obtained in this study and those published in the past.This invasive pest represents a major potential threat to agri-horticulture in Shandong,which is a key province of China for production and export of many vegetables,flowers,fruits,and other crops.This mealybug species has a wide range of potential distribution in Shandong and is easily dispersed with agricultural and horticultural transport products.Further monitoring and management strategies are required to limit the spread of this pest species.

Species-specific COI primers for rapid identification of a globally significant invasive pest, the cassava mealybug Phenacoccus manihoti Matile-Ferrero

The globally invasive cassava mealybug Phenacoccus manihoti Matile-Ferrero is a pernicious pest of cassava,and its recent introduction into Asia has raised considerable alarm.To slow or prevent further invasion,an accurate,simple,and developmental-stage-independent detection method for P.manihoti is required.In the present study,a PCR method based on a species-specific mitochondrial DNA cytochrome oxidase I(SS-COI)marker was developed for rapid identification of P.manihoti.One pair of SS-COI primers(PMSSZW-1F and PMSSZW-1R)was designed based on sequence variations in the COI gene among P.manihoti and related mealybug species.Specificity of the primer pair was validated on 21 closely related species.Sensitivity tests were performed on four immature developmental stages and female adults.Efficacy tests demonstrated that at the relatively low concentration of(135.2±14.7)pgresuspended DNA,the specific fragment was detected in all replicates.Furthermore,the SS-COI primer pair was assayed on three populations of P.manihoti from major exporting countries of cassava.The PCR assay was proved to be a rapid,simple,and reliable molecular measure for the identification of P.manihoti.This tool will be useful for quarantine,monitoring,and management of this invasive pest.

扶桑绵粉蚧的识别及防治

扶桑绵粉蚧在广东、广西、海南和浙江等省甘薯上危害严重,为了精准识别和有效防控扶桑绵粉蚧,详细介绍了扶桑绵粉蚧的特征特性、分布与危害、危害症状、发生特点,并结合实践提出了植物检疫、农业防治、物理防治、生物防治、化学防治等综合防治方法。

A new species and a new record of the genus Balanococcus Williams(Hemiptera:Coccoidea:Pseudococcidae) from China

A new species and a new record of the genus Balanococcus Williams are described from China. They are B. zhejiangensis sp. nov. and B. kwoni Pellizzari ＆ Danzig, 2007. The new species, collected from Zhejiang, China under leaf sheath of Phyllostachys praecox, is similar to B. kwoni Pellizzari ＆ Danzig, but can be distinguished by its hind coxa inflated, and only small type of oral collar tubular ducts present on dorsal surface. A key to Chinese species of Balanococcus is given. All specimens examined are deposited in the Insect Collection of Beijing Forestry University.

中国绵粉蚧属（Phenacoccus Ckll．）的分类研究

绵粉蚧属ＰｈｅｎａｃｏｏｃｕｓＣｋｌｌ是粉蚧科内一个古老属，也是一个大属。世界范围分布，生活在木本和草本植物的根部和叶上，是林木、果树和花卉等的重要害虫。作者在广泛采集和对本校蚧虫室所积累的全国各地标本观察研究的基础上，对我国以往所记录过的种类进行了评价，共整理出中国本属８个种类，对它们的形态，分类检索作了详细研究。此外，还概述了本属研究历史等。

The Chinese species of the mealybug genus Neotrionymus Borchsenius(Hemiptera： Coccoidea： Pseudococcidae)

The genus Neotrionymus Borchsenius comprises five species in China, N. cynodontis, N. guandunensis, N. monstatus, N. yunnanensis and N. chinensis sp. nov., which collected from Beijing, Shanxi and Shandong under the leaf sheath of species of Poaceae. This new species is similar to N. kerzhneri Danzig, but can be distinguished by with a large, quadrate（longer than width） or sometimes hour-glass shaped circulus, presence of tubular ducts in median area of thorax on dorsum and venter, presence of translucent pores on apical part of hind tibia and the distribution of trilocular pores not only in cerarii, but also on lips of ostioles and near spiracles. A key to species of genus Neotrionymus in China is also given.

5种药剂对不同发育阶段白蜡绵粉蚧Phenacoccus fraxinus的室内毒力

白蜡绵粉蚧Phenacoccus fraxinus Tang是白蜡Fraxinus chinensis Roxb.的一种重要害虫。为筛选出高效防治白蜡绵粉蚧的药剂,本试验采用浸渍法测定了5种药剂对不同龄期白蜡绵粉蚧的毒力。测试的5种药剂对白蜡绵粉蚧1龄若虫致死中浓度为18.48~24.52 mg/L,均表现较高的毒力。对2龄若虫和成虫的致死中浓度分别为18.48~76.25 mg/L和44.00~79.53 mg/L,毒力稍低于1龄若虫。但5种药剂对白蜡绵粉蚧3龄若虫的毒力明显低于其他龄期,除20%丁硫克百威乳油毒力较高(42.00 mg/L)外,其余4种药剂的致死中浓度为97.73~132.24 mg/L。因此,5种药剂对白蜡绵粉蚧1、2龄若虫和成虫毒力较强且稳定,均可作为防治白蜡绵粉蚧低龄若虫和成虫的优良药剂,但3龄若虫最好选用毒力较高的20%丁硫克百威乳油进行防治。

Analysis of expressed sequence tags （ESTs） from a normalized cDNA library and isolation of EST simple sequence repeats from the invasive cotton mealybug Phenacoccus solenopsis

The cotton mealybug, Phenacoccus solenopsis Tinsley, is a serious and invasive pest. At present, genetic resources for studying P. solenopsis are limited, and this negatively affects genetic research on the organism and, consequently, translational work to improve management of this pest. In the present study, expressed sequence tags （ESTs） were analyzed from a normalized complementary DNA library of/？. solenopsis. In addition, EST-derived microsatellite loci （also known as simple sequence repeats or SSRs） were isolated and characterized. A total of 1107 high-quality ESTs were acquired from the library. Clustering and assembly analysis resulted in 785 unigenes, which were classified functionally into 23 categories according to the Gene Ontology database. Seven EST-based SSR markers were developed in this study and are expected to be useful in characterizing how this invasive species was introduced, as well as providing insights into its genetic microevolution.

4种植物源杀虫剂对扶桑绵粉蚧毒力及龟纹瓢虫安全评价

探索4种植物源农药对入侵害虫扶桑绵粉蚧的毒力,评价其对龟纹瓢虫卵及成虫的安全性,为扶桑绵粉蚧的绿色防控提供理想药剂和理论依据。采用喷雾法测定4种植物源杀虫剂对3龄扶桑绵粉蚧的毒力和龟纹瓢虫卵的孵化率影响,采用滤纸接触法测定2种对扶桑绵粉蚧高效的植物源杀虫剂对天敌龟纹瓢虫成虫的毒力,并评价其对龟纹瓢虫的安全性。结果表明:4种植物源杀虫剂处理扶桑绵粉蚧3龄幼虫24 h后的毒力由高到低依次为1.3%苦参碱AS(LC_(50)为81.2831 mg/L)>0.5%藜芦碱SL(LC_(50)为112.8811 mg/L)>2.5%鱼藤酮EC(LC_(50)为208.9296 mg/L)>5%桉精油SL(LC_(50)为343.0920 mg/L);与化学对照药剂22.4%螺虫乙酯EC相比,相对毒力指数由高到低依次为1.3%苦参碱AS(3.3025)>0.5%藜芦碱SL(2.3780)>2.5%鱼藤酮EC(1.2048)>5%桉精油SL(0.7824);几种杀虫剂的田间最大推荐剂量和对扶桑绵粉蚧的LC_(50)剂量处理龟纹瓢虫卵后,孵化率差异不显著;苦参碱AS和藜芦碱SL对龟纹瓢虫成虫的LC_(50)高于对扶桑绵粉蚧的LC_(50);结合益害毒性比和安全系数,2种药剂对龟纹瓢虫卵和成虫安全。该实验筛选出1.3%苦参碱AS和0.5%藜芦碱SL对扶桑绵粉蚧有明显的控害作用,且对龟纹瓢虫卵和成虫的毒性较小、安全性较高,可作为扶桑绵粉蚧的绿色防控的理想药剂。

50%呋虫胺对入侵害虫扶桑绵粉蚧的室内毒力及田间药效

【目的】为评估50%呋虫胺水分散粒剂对扶桑绵粉蚧的防治效果。【方法】采用喷雾法进行50%呋虫胺水分散粒剂的室内生物测定和田间药效试验。【结果】3龄幼虫、成虫的致死中浓度LC50值分别为25.8297 mg/L、49.5898 mg/L,显示了对扶桑绵粉蚧有较强的毒力。田间药效试验显示,相同的处理时间,呋虫胺对扶桑绵粉蚧的防效与浓度呈正相关;C1(0.125 g/L)、C2(0.167 g/L)处理在药后7 d达到最高防效,14 d后防效下降;C3(0.2 g/L)、C4(0.25 g/L)和C5(0.5 g/L)防效与药剂浓度和处理时间呈正相关,C5的防治效果最好,药后3 d、7 d的校正防效显著高于其他浓度的同期效果,药后14 d的防效为92.08%,显著高于C1、C2和C3,与C4差异不显著。【结论】研究表明,50%呋虫胺水分散粒剂可有效防治扶桑绵粉蚧。在进行防治时,综合考虑防治效果、防治成本及生态环境保护等因素,建议使用C4进行防治,当绵粉蚧虫口基数较大时,可在药后10~14 d进行2次用药。

木芙蓉上亚利桑那跳小蜂对扶桑绵粉蚧的寄生研究

扶桑绵粉蚧Phenacoccus solenopsis Tinsley是我国重要观赏和药用植物木芙蓉上的主要害虫之一,但迄今对其被优势天敌亚利桑那跳小蜂Aenasius arizonensis (Girault)(班氏跳小蜂A.bambawalei Hayat)的寄生情况了解甚少。为此,自2017年开始,在浙江兰溪西部的一个木芙蓉种植区开展了为期四年的调查,每年6—9月,分批从木芙蓉植株上采集3龄若虫及未产卵雌成虫,于室内观察寄生情况;并于其中两年观察了不同生境中的寄生情况,探讨了寄生季节变化的动态特征及相关影响因素、杂草促进寄生的途径以及增强该粉蚧自然控制的措施。结果表明,在前期(6—7月)寄生率总体上较低,其中两年最高分别仅有38%和32%,另外两年也很少发现被寄生个体,而且该时期寄生率年份间存在明显波动。而在后期(8—9月),寄生率相对较高,且具有从8月上旬开始逐步上升这一显著特点。观察期间,最高寄生率均出现于各年份9月下旬,四年中分别为89%、62%、55%和13%,年份间差异十分明显。生境类型可对寄生水平产生较大影响,与木芙蓉地块内和杂草稀疏的田埂相比,杂草丛生的田埂上和路边区域中粉蚧被寄生率相对较高;另外,在毗邻田块的路边地段,9月上旬的寄生比例一定程度上高于距离木芙蓉地块较远的路边地段。本研究表明,木芙蓉上亚利桑那跳小蜂对扶桑绵粉蚧的控制作用随年份和季节剧烈变化,一些生境诸如杂草较多的地段有利于增强其控害作用。

类黄酮合成通路介导的木薯对木薯绵粉蚧的防御机理

木薯是世界重要的粮食作物、能源作物和工业原料。木薯绵粉蚧(Phenacoccus manihoti Matile-Ferrero)是一种世界危险性检疫性害虫,培育和利用抗虫木薯品种可以有效阻断其定殖为害。挖掘具有抗虫作用的次生代谢物质及其调控基因是开展抗虫育种的重要策略之一。而类黄酮是植物抵御生物与非生物胁迫的特有次生代谢物质,但类黄酮及其合成通路基因在木薯抗木薯绵粉蚧中的功能尚不清楚。据此,本研究分析了抗虫木薯品种(C1115、SC9、缅甸)和感虫木薯品种(KU50、SC205、面包)被木薯绵粉蚧为害不同时间(0、1、4、8d)后,叶片中类黄酮合成通路相关基因(CHS、CHI、FLS、LAR、DFR、F3H、CCoAOMT、C4H、C3’H、ANR)表达量以及类黄酮含量的变化情况。结果表明:木薯绵粉蚧取食后,叶组织中CCoAOMT、C3’H、ANR、C4H虽然上调表达,但与为害前相比并无显著差异,且抗、感木薯品种间的表达量也无显著差异;与之相对,CHS、CHI、FLS、F3H、DFR、LAR基因表达量均比为害前显著提高,并且在相同的为害时间内,这6个基因在抗虫木薯品种中的表达量也显著高于感虫木薯品种。进一步通过相关性分析发现,CHS、CHI、FLS、F3H、LAR基因的表达量与木薯品种的抗虫性呈显著正相关。此外,总黄酮含量测定结果表明:木薯绵粉蚧为害1 d时总黄酮含量与为害前相比均显著上升,为害4 d后抗虫木薯品种总黄酮含量显著高于感虫木薯品种。相关性分析显示,总黄酮含量也与木薯品种的抗虫性呈显著正相关。因此推测,类黄酮含量的上升及其调控基因CHS、CHI、FLS、F3H、LAR在抗虫木薯品种中的显著上调表达与其对木薯绵粉蚧的抗性有关。本研究为深入解析类黄酮合成基因调控木薯对木薯绵粉蚧的抗虫防御反应分子机制,以及木薯抗虫分子设计育种提供重要的前期基础。

扶桑绵粉蚧在烟草上的适合度和药剂筛选研究

为明确扶桑绵粉蚧在烟草上的适合度并筛选出有效防治药剂,室内条件下测定了扶桑绵粉蚧在雪茄烟H382和烤烟NC89上的发育历期、寿命、生殖力等重要适合度参数,并采用浸叶法测定了10种药剂对该虫的毒力。结果显示,扶桑绵粉蚧在2种供试烟草上均可完成生活史,与H382相比,扶桑绵粉蚧在NC89上的发育历期更短、雌成虫寿命更长、生殖力更高;2龄若虫选择NC89的比例更高,在NC89上的种群建立率和瞬时增长率ri也高于在H382上的。10种供试药剂对扶桑绵粉蚧的毒力差异较大,其中高效氯氟氰菊酯对扶桑绵粉蚧3龄若虫及雌成虫的毒杀效果最好,LC50分别为1.331 mg/L和2.826 mg/L,氟吡呋喃酮、烯啶虫胺及氟啶虫胺腈对若虫和成虫的毒杀效果也较好,氟啶虫酰胺的毒杀效果最差。本研究发现2种供试烟草均是扶桑绵粉蚧的适宜寄主植物且NC89的适合度更高,筛选出的毒力较高药剂可作为该虫应急化学防控的候选药剂。

扶桑绵粉蚧虫生真菌FE-1菌株的鉴定及其毒力测定

【目的】评价从扶桑绵粉蚧(Phenacoccus solenoposis)僵虫中分离的虫生真菌在害虫生物防治中的应用潜力,为开发其作为生物防治制剂提供基础。【方法】采用组织分离法,从扶桑绵粉蚧僵虫中分离纯化虫生真菌菌株,综合培养性状、形态学特性和系统发育树分析,明确其分类学地位;利用扫描电镜技术,探究菌株对扶桑绵粉蚧的侵染方式,明确其对扶桑绵粉蚧的侵染力;采用浸虫法,室内测定分离菌株对扶桑绵粉蚧雌成虫的致病力。【结果】从扶桑绵粉蚧僵虫中分离纯化获得一株真菌菌株FE-1,形态学结果发现菌株FE-1在PDA培养基培养5 d后菌落直径为50~60 mm,菌落正面为橙白色,分生孢子形态呈两种类型,小型孢子为长柱形,大型孢子为镰刀型;综合培养性状、形态学特征和系统发育树分析结果鉴定菌株FE-1为木贼镰刀菌(Fusarium equiseti);扫描电镜结果表明菌株FE-1侵染扶桑绵粉蚧的方式主要为分生孢子在表皮处萌发形成芽管,然后水平生长,并在特定接触表皮处形成膨大的附着孢进入昆虫体腔,明确了菌株FE-1对扶桑绵粉蚧侵染力;室内毒力测定结果表明,菌株FE-1对扶桑绵粉蚧雌成虫的致病力随着分生孢子浓度的增大逐渐增强;孢子浓度为1×10^(8)CFU/mL时,LT_(50)为3.32 d,接种7 d后,扶桑绵粉蚧雌成虫的校正死亡率为87.50(±1.79)%,LC_(50)为1.8×10^(5)CFU/mL。【结论】从扶桑绵粉蚧僵虫中分离纯化获得的木贼镰刀菌菌株FE-1,其在扶桑绵粉蚧体壁能形成膨大的附着孢进行侵染,对扶桑绵粉蚧具有一定的侵染力。同时,该菌株在室内对扶桑绵粉蚧雌成虫有较好的致死效果,极具生防潜力,可为扶桑绵粉蚧的生物防治研究提供优质的原材料。

鄱阳湖地区扶桑绵粉蚧寄主植物调查及寄生蜂鉴定

【目的】为明确扶桑绵粉蚧Phenacoccus solenopsis在鄱阳湖地区发生危害情况,掌握其寄生性天敌的种类、寄生特点及生态控害功能。【方法】对鄱阳湖周边地区扶桑绵粉蚧及寄生天敌概况进行随机抽样调查,采用形态学结合mtCOⅠ基因序列分析对寄生蜂鉴定分析。【结果】该地区扶桑绵粉蚧发生较为普遍,寄主植物种类较多,共涉及26科59种,棉花、胡麻等大田经济作物发生较重,辣椒等部分蔬菜、马齿苋等部分杂草类也是该虫的偏好型寄主;扶桑绵粉蚧寄生蜂共有2科4个种,分别为跳小蜂科的班氏跳小蜂Aenasius bambawalei、南京刷盾跳小蜂Cheiloneurus nankingensis、缘长原跳小蜂Prochiloneurus sp.和蚜小蜂科的豹纹花翅蚜小蜂Marietta picta,其中班氏跳小蜂是初级寄生蜂的优势种,其余3种均为重寄生蜂,而南京刷盾跳小蜂为重寄生蜂的优势种。班氏跳小蜂与南京刷盾跳小蜂的寄生僵蚧所占比例分别为47.91%、32.89%,孵化出的寄生蜂分别为126头、751头,出蜂数占全部寄生蜂总量的13.26%、79.05%,且南京刷盾跳小蜂始终伴随班氏跳小蜂的发生而发生,对后者控害功能具有巨大的干扰作用。通过Kimura2-Parameter(K2P)计算4种寄生蜂的mtCOⅠ序列的遗传距离为0.0602~0.3355,总平均遗传距离0.1026。【结论】基于鄱阳湖地区扶桑绵粉蚧发生的普遍性,利用班氏跳小蜂的寄生功能,是控制扶桑绵粉蚧种群数量的重要方法,但降低南京刷盾跳小蜂的重寄生干扰,是发挥班氏跳小蜂生态控害功能的关键。

海南主要粉蚧种类及危害

为了探明海南主要粉蚧的种类及危害状况,通过对海南各县市的各类热带水果、经济作物、绿化植物及花卉等上发生的有害粉蚧进行野外调查和分类,共鉴定出海南主要粉蚧10属21种。通过对21种粉蚧基础信息的梳理,明确了土著种13种、入侵种8种、海南新纪录2种。

绵粉蚧危害的花椒树对异色瓢虫的招引作用

1999— 2 0 0 1年研究了山西太行山区花椒林受绵粉蚧危害后 ,花椒树对主要天敌昆虫异色瓢虫的招引作用。结果显示 ,花椒树受害的新鲜枝梢对瓢虫的引诱率为 5 7 0 % ,未受害新鲜枝梢引诱率为 2 0 0 % ,用受害枝条水浴蒸馏出的馏分招引瓢虫的百分率为 37 0 % ,未受害枝条馏分招引瓢虫百分率为 10 3%。说明花椒绵粉蚧危害 ,可诱导树体挥发性物质发生改变 ,增加了对天敌昆虫的引诱作用 ,并且对瓢虫的引诱力随着受害枝梢量的增加而增强 ,它的诱导活性在受害后可持续约 2个月 ;采用GC MS联用仪分析比较 ,发现受害花椒枝梢的酯类物质明显增多 ,受害与未受害花椒枝梢的气相色谱图中有 15个峰位的化学组分相同 ,但受害的含量显著高。另有 9个峰位的组分在未受害枝梢中含量太低 ,未检测出。